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Stock-based compensation - Changes in Restricted Stock Units (Details) - $ / shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Aug. 15, 2020
Franklin Financial Network, Inc. |  |  |  |
Weighted Average Grant Date Fair Value |  |  |  |
Replacement awards issued to employees (in shares) |  |  |  | 118,776
RSUs |  |  |  |
Restricted Stock Units Outstanding |  |  |  |
Balance at beginning of period (in shares) | 826,263,000 |  |  |
Granted (in shares) | 420,521,000 |  |  |
Vested (in shares) | (177,581,000) |  |  |
Forfeited (in shares) | (22,132,000) |  |  |
Balance at end of period (in shares) | 1,047,071,000 | 826,263,000 |  |
Weighted Average Grant Date Fair Value |  |  |  |
Balance at beginning of period (in USD per share) | $ 23.76 |  |  |
Granted (USD per share) | 31.35 | $ 34.08 | $ 39.55 |
Vested (USD per share) | 31.64 |  |  |
Forfeited (USD per share) | 33.20 |  |  |
Balance at end of period (in USD per share) | $ 26.06 | $ 23.76 |  |

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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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